Grayling is the fine, white, faintly sweet flesh of the European grayling (Thymallus thymallus), a freshwater salmonid of cold, clean rivers across northern and central Europe. Famous among anglers for its towering, sail-like dorsal fin and its violet sheen, the fresh fish is said to carry a delicate scent of wild thyme — the trait that gave the genus its name, Thymallus.